1. Field of the Invention
The present invention relates generally to automatic vehicle washing systems and, more particularly, to a new and improved reciprocating gantry-type washing system designed to efficiently wash the top, front, rear and sides of a vehicle.
2. Background of the Invention
There are many techniques for washing vehicles without conventional hand scrubbing. Perhaps the most common washing system is the tunnel-type car wash system wherein a vehicle to be washed is passed through a series of linearly spaced cleaning stations. Each cleaning station executes a different sequential cleaning operation such as pre-soaking, rinsing, scrubbing, waxing, and related operations. However, although tunnel-type washes are generally considered to be effective in washing vehicles, tunnel-type washes may be detrimental to a vehicle's finish.
In some conventional tunnel-type wash systems, "mitter curtains" comprised of strips of cloth that are rocked back and forth transversely across the path of the vehicle, abrasively scrub dirt and other debris from the surface of the vehicle. Alternately, or in combination with a mitter curtain, revolving brushes may rotatably engage the surface of the vehicle. In either case, the vehicle surface may be scratched by contact with granular dirt particles that may have collected on the mitter curtains or brushes, and/or may contact with the brushes or curtains themselves.
Alternately, "brushless car washes" do not scratch the surface of vehicles because no parts of the brushless car wash contact the surface of the vehicle. Instead of using mitter curtains or brushes, brushless car washes spray clean exterior surfaces of a vehicle with pressurized fluid jets that are passed adjacent to the surface of the vehicle. The jets are arrayed in a washing frame which revolves around the vehicle or passes linearly along the vehicle, or the frame may be kept stationary while the vehicle is passed through the frame. In any case, the object is to submit the entire readily visible exterior surface of the vehicle to the spray jets to remove dirt and grease from the vehicle surface.
Unfortunately, the cleaning ability of the system is largely dependent upon the pressure generated by the jet sprays, and the further away the spray jets are from the vehicle, the less fluid pressure is delivered to the vehicle surface. Accordingly, those parts of the vehicle which are furthest from the washing frame may not be adequately cleaned. Improved automated systems have been devised for moving the washing frame along a curved track in front and behind the vehicle to minimize the problem but such systems may be costly because they typically are mechanically more complex and/or must be suspended from an overhead surface.
Systems have also been devised for spraying after-wash conditioning liquids or foams onto the surface of a vehicle to protect the surface. An example of such a system is disclosed in U.S. Pat. No. 5,575,852 issued to Chase. In this system, a plurality of inverted L-shaped tubes are mounted on a gantry-type car wash system with each tube having a mixing zone adjacent the top center of the gantry, a buffer zone at an elbow of the tube, and a fluid delivery zone extending vertically downwardly along the side of the vehicle being washed. A mixture of chemical solution and air is introduced to the mixing station and then delayed through the buffer zone before being delivered to the discharge zone from which the pressurized chemical solution is sprayed onto the side of the vehicle through spray nozzles. Such systems are somewhat clumsy and awkward to mount since they extend across the top of the gantry as well as down its sides and, further, are fairly long in length due to the required buffer zone between the mixing and discharge zones. The afore-noted patent has addressed the clumsiness of the system by incorporating the buffering zone in one embodiment into the mixing zone but in either event, the tubes still relatively long and extend horizontally across the top and vertically along the sides of the gantry.
Another prevalent drawback of conventional brushless systems resides in the fact that they typically have spray nozzles disposed along the sides of the vehicle adapted to spray pre-soak or other cleansing solutions substantially perpendicularly at the sides of the vehicle. Since the nozzles are oriented perpendicularly to sides of the vehicle, they do not provide sufficient coverage on the front and rear surfaces of the vehicle and, therefore, typically the wash system will have to make a pass in each direction along the length of the vehicle so that the front and rear of the vehicle are sprayed twice in an attempt to get a sufficient amount of solution onto the surfaces for adequate cleansing of the car. Making a double pass, of course, is time consuming and also is a waste of solution to the extent that it is sprayed twice on the sides of the vehicle where adequate coverage should be obtainable in one pass.
It is an object of the present invention to overcome the afore-noted shortcomings in prior art car wash systems.